Apparatus for protecting inflammable liquids against fire



Sept. 14, 1948. c. E. BENNETT 2,449,270 APPARATUS FOR PROTECTINGINFLAMMABLE LIQUIDS AGAINST FIRE Filed Sept. 29, 1944 g lNVENTgR W?tente et. id, i-

"I'US FOR PROTECTING :r a .1

-= LE LIQUIDS AGAINST i i -l- Charles E. Bennett, Ridgewood. n. a

Application September 29, 1944, Serial No. 556,437

1 Claim. (on. icematic in operation, adapted to prevent fire orextinguish fire in closed containers of inflammable liquids such as oil.

More specifically my invention provides an attachment adapted to beinstalled upon both existing and new equipment, and capable ofautomatically discharging a non-inflammable material into the liquid tobe protected against fire, from beneath'the surface of the same. Thisnoninfiammable material is very miscible with the liquid to be protectedand inasmuch as it is stored under pressure, it will, upon release,quickly permeate the entire body of the liquid and blanket any firewhich may be present at the surface thereof.

The accompanying drawing illustrates an embodiment of my invention inpart sectional elevation. 7

Referring to the drawing in detail: 2 designates a tank containing aliquid which it is desired to protect against fire. This tank may be anelectrical transformer tank, for instance, in which event the liquid tobe protected will be transformer oil, which is highly inflammable.

It is to be understood, however, that my invention is equally applicableto other types of equipment and other liquids, as will be explainedhereinafter. v

6 designates a tube within the tank 2. This tube is preferably installedfairly close to one sidewall of the tank, and extends downwardly to apoint adjacent the bottom of the tank, and is there bent outwardly awayfrom the tank wall so that its discharge end is approximately in thecenter line of the tank. This end of the tube is equipped with checkvalve 8, which opens outwardly of ,the tube.

At the exterior of the tank 2 adjacent the top thereof, and suspendedfrom spring balance or other type of weight indicator 8 is an invertedbottle ill of dichlorodifiuoromethane (CClzFz). Flexing tubing [2 isattached to the lower end, the discharge end of this bottle, and iscoupled to the upper end of tube a Adjacent its upper end, at the pointof maximum temperature in the event of a fire within the tank 2, thetube d is provided with a temperature controlled stop or dam, forpreventing, under normal conditions, the passage of thedichlorodifiuoromethane along the tube. This temperature controlleddevice may be a standard sprinkler head, a diaphragm such asillustrated. 4

or other suitable device which will function to release thedichlorodlfluoromethane in the event of a fire. For purposes ofillustration I have shown a diaphragm, composed of an alloy of lead,

The dichlorodifiuoromethane is under a pressure of the order of 70 lbs.per square inch, and under this pressure and at about 70 F. it isliquid. This material is very highly miscible in the transformer oil.

It will be evident from all of the foregoing that upon a rise intemperature of the oil in-the tank to the flash-point of the oil, thetemperaturecontrolled device it, in this case a diaphragm, will functionto release the dichlorodifiuoromethane into the bottom of the tank 2. Asthis material is released, it will revert to a gas and some of it bubbleto the surface of the oil and blanket the fire. A great deal of thegaseous dichlorodifluoromethane, however, being highly miscible with theoil will remain in solution in the oil to convert the oil to anon-inflammable mixture of oil and dichlorodifiuoromethane.

The function of the spring balance or other weight indicator 8 is toindicate to the operating staff when my apparatus has functioned.

As above noted my apparatus is usable in connection with preventingfires in. any liquid in which the dichlorodifiuoromethane is miscible,and my invention is not confined merely to protecting insulating oils.

As above explained, my invention is not limited to the use of a fusiblediaphragm, such as shown at it, for a temperature controlled device forreleasing the dichlorodifiuoromethane.

It is to be understood that other changes may be made in the details ofconstruction and arrangement of parts hereinabove described withoutdeparting from the spirit and scope of m invention.

What I claim is:

In combination with a tank of inflammable liquid, a container ofdichlorodifiuoromethane at the exterior of the tank and under sufficientpressure to maintain the dichlorodifiuoromethane in the liquid phase, atube extending from the container into the tank near the top thereof andalong the tank wall to a point adjacent the bottom of the tank andthence inwardly of the tank to approximately the center line of thetank, and a fusible diaphragm across said tube adjacent the surface ofthe inflammable liquid, said diaphragm fusing at substantially theflashpoint of said inflammable liquid. whereby upon a rise in thetemperature of the inflammable liquid at its surface approximating itsflashpoint the dichlorodifluoromethane will be released into the liquidadjacent the bottom thereof, some of the dlchlorodifluoromethaneremaining in solution in the inflammable liquid to convert the liquid toa. non-inflammable mixture of liquid and dichlorodifluoromethane, theremainder of the dichiorodifiuoromethane rising to the surface of theliquid.

CHARLES E. BENNETT.

REFERENCES CITED The following references are oi record in the file ofthis patent:

Number Number UNITED STATES PATENTS 7 Name Date Burritt July 5, 1881Monch July 8, 1884 Erwin- Dec. 28, 1926 Bichowsky Nov. 26, 1935 HeigisDec. 6, 1938 FOREIGN PATENTS Country Date Great Britain Oct. 20, 1880Austria June 25, 1920

